FIELD OF THE INVENTION
This invention relates to a high compression ratio internal-combustion engine which locates the control valve in sub-chamber.
The higher compression ratio (.epsilon.) usually leads to increased performance of the engine.
Therefore, the gasoline engine drives the compression ratio at about 8-10.
The engine cannot demonstrate enough performance when this compression ratio is further increased, generating a knock in the combustion cylinder of the engine.
In a diesel engine, the fuel is ejected into the air, compressed in the combustion cylinder and burns.
Therefore, the diesel engine increases the compression ratio to about 18-23 and improves the performance.
The gasoline engine mixes the fuel with air and makes a so-called pre-mixture beforehand, outside the engine and injects this in the cylinder as described.
When the compression ratio of the gasoline engine is raised to more than 8-10 and the temperature of the compressed air in the combustion cylinder is raised. Furthermore, the pre-mixture gas injected into the combustion cylinder ignites and a knock is generated, before the spark is ignited.
It is difficult for the gasoline engine to improve the compression ratio more than an old value.
The fuels of the engine are the fossil fuels such as gasoline, light oil and natural gas.
When these fossil fuels are used for the fuel of the engine, a lot of materials which pollute the atmosphere such as nitrogen oxide and soots are included in exhaust gas.
The engine which burns methanol can be developed which creates little pollution.
As mentioned above, the content of soot and the nitrogen oxide in exhaust gas decreases when the methanol is used for the fuel of the engine.
When the load of the engine is high, a lot of problems are not caused. However, with a low engine load, the wall temperature of the combustion cylinder decreases because the latent heat of evaporation of the methanol is large and the ignition temperature is high.
Therefore, evaporation and the activation of the methanol become difficult and the combustion cylinder of the engine is not burnt smoothly.